This invention is in the field of sewing machines; more particularly, it is concerned with a thread cutter for a sewing machine.
In certain of the prior art, there are disclosed thread cutters which may be attached to existing sewing machines so that an operator may readily cut the thread extending from a stitched article without the necessity for locating scissors or other thread cutting implements. Such devices are disclosed in the U.S. Pat. No. 2,867,184 and in the Italian Patent No. 642111 as well as in the Japanese U.M. Application No. 17470. The former two devices are designed for attachment by the presser foot retaining thumb screw, and the Japanese U.M. application is designed for attachment to the sewing machine face plate above the sewing needle.
There is also disclosed in U.S. Pat. No. 1,195,834 of Mathews, a thread cutting blade having a lug extending through a slot in a bed slide, which lug may be used to deflect thread drawn therebeneath into the slot and to the cutting edge of the blade. However, being located on the sewing machine bed adjacent the stitching point, as it is, there may be some interference with progress of work material across the sewing machine bed. Also, a short thread end may result, which could cause unthreading of the sewing needle. The U.S. Pat. No. 2,781,012 of Kuhar, discloses a thread cutting slot cut into the presser bar bushing beneath the head of the sewing machine. However, great care must be exercised in cutting this slot to insure its effectivness in cutting the sewing machine threads. On the other hand, if the slot is effective to cut sewing threads, it might also be effective to cut an operator's finger drawn across that surface.
What is required is a thread cutter arrangement which is always effective for its intended purpose but does not adversely effect the appearance of the sewing machine. Ideally, the thread cutter should be concealed and inaccessible except by sewing thread for the sake of safety to prevent harm to an operator or user of the sewing machine.